Tape cassette arrangement

Abstract

A tape cassette arrangement comprises a supply reel and a take up reel and control means acting upon the take up reel to prevent unauthorized rewinding of the tape. The control means comprises a pawl which engages the take up reel in the tape unwinding direction and a slidable mechanism which releases the pawl from the toothed periphery of the reel. To permit authorized rewinding of the cassette, the ratchet may be dissengaged by moving the controlling mechanism with a tool inserted into an aperture in the cassette housing. To prevent a knowledgable user from inserting a tool into the aperture and playing, rewinding and playing, the cassette over and over again, a second pawl is mounted to engage the supply reel stopping its rotations in the tape playing direction. The second pawl is engaged when a rewinding tool is inserted into an aperture in the cassette housing. A counter is connected to the control mechanism to record the number of times the tape is played.

I claim: 
     
       1. A single play tape cassette driven by a playing apparatus comprising: a take up reel and a supply reel having a tape movable therebetween, each of said reels having toothed peripheral portions,   first mounting means, a first pivotly mounted pawl mechanism mounted thereto having a first pawl arm mounted for engagement with the toothed peripheral portion of the take up reel and a first finger integral with the first pawl and located at an angle thereto and mounted in engagement with the take up reel, and second mounting means, a second pivotally mounted pawl mechanism mounted thereto having a second pawl arm mounted for engagement with the toothed peripheral portion of the supply reel, and a second finger integral with the second pawl and mounted in engagement with the supply reel, wherein the first pawl is actuated by the first finger to prevent rotation of the take up reel in a rewinding direction, and the second pawl is actuated by the second finger to prevent rotation of the supply reel in an unwinding direction,   control means mounted within the cassette to selectively disable the first or the second pawl mechanisms to allow rotation of the supply reel in the unwinding direction or to allow rotation of the take up reel in the rewinding direction, and   means to engage the control means to cause it to disable one of the pawl mechanisms.   
     
     
       2. A single play tape cassette in accordance with claim 1 wherein: the control means comprises support means, an elongated slidable member mounted on the support means for movement therealong, said slidable member having protruding two end portions which each engage and disable one of the pawl mechanisms at either selected end of the slidable member and a downwardly extending member including a first sloped forward surface and a rear vertical surface and,   a spring engaging said rear surface to maintain the control mechanism in a neutral position.   
     
     
       3. A single play tape cassette in accordance with claim 2 further including: a counter coupled to the control means to record the number of times the control means are moved.   
     
     
       4. A single play tape cassette in accordance with claim 2 wherein the supply reel and the take up reel each include flange portions, and,   the first integral finger and the second integral finger each include a frictional surface which engages the flange portion of the take up reel and supply reel respectively to move the pawl mechanisms upon rotation of the respective reel in a predetermined direction.   
     
     
       5. A single play tape cassette in accordance with claim 2 wherein the first and second pawl mechanisms each include a pivot portion having a notch for engagement with the slidable member of the control mechanism, the pawl arm extending outwardly from the pivot position and the integral finger extending outwardly at substantially a right angle to the ratchet arm.